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A THERMAL HEATED LUNCH BOX
TAN KIEN GUAN
This report is submitted as partial fulfillment Of requirements for the award Bachelor of Mechanical
Engineering (Thermal-Fluids)
Faculty of Mechanical Engineering Universiti Teknikal Malaysia Melaka
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SUPERVISOR DECLARATION
“I hereby declare that I have read this thesis and in my opinion this report is sufficient in terms of scope and quality for the award of the degree of
Bachelor of Mechanical Engineering (Thermal-Fluids)”
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DECLARATION
“I hereby declare that the work in this report is my own except for summaries and quotations which have been duly acknowledged.”
Signature:... Author :Tan Kien Guan
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To my beloved parents, My siblings
And also
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Acknowledgement
First of all, I would like to thank Universiti Teknikal Malaysia Malaka. It is an opportunity that allows students to apply what they have learned in their academic study for the past few years. It also gave me the chance to sharpen my thinking and gain knowledge as well as practical skill that will be useful in the future.
I would like to take this chance to thank my supervisor, Dr. Tee Boon Tuan, whose encouragement, guidance and support from the initial to the final stage had enabled me to develop an understanding of the final year project. He gave me useful advice throughout the whole final year project and helped me indentify my weaknesses which of had managed to overcome.
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ABSTRACT
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ABSTRAK
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1.5 Basic characteristic of lunch box 3
1.5.1 Material 3
1.5.2 Storage space 4
1.5.3 Food protection 4
1.5.4 Temperature resistance 4
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1.5.6 Mobility 5
2. CHAPTER 2 (REVIEW OF LITERATURE) 6
2.1 Introduction 6
2.2 Thermoelectric cooler peltier 7
2.3 Thermodynamic 8
2.3.1 Fourier law of heat conduction 8
2.3.2 Newton law of cooling 9
2.4 Material selection 10
2.4.1 Characteristic of plastic 11
2.5 Aluminium foil 11
2.5.1 Characteristic of aluminium foil 12
2.6 Electronic component 12
3.2 Comparison lunch box product 21
3.3 Configuration design 22
3.4 Weighted decision matrix 24
3.5 Conceptual design 26
3.6 Actual design 26
3.7 Material selection process 28
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4.3.2 `Electronic installation (Soldering) 42
4.4 Assembly 44
4.5 Programming and PIC 45
4.6 Testing 46
5. CHAPTER 5 (Experiment of Performance and Discussion) 47
5.1 Introduction 47
5.2 Experiment of performance 48
5.2.1 Performance of thermoelectric cooler peltier 48
5.3 Modeling heat flux and natural convection 54
5.9 The differential real design and the conceptual design 64
6. CHAPTER 6 (Recommendation and Conclusion) 67
6.1 Conclusion 67
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REFERENCES 69
APPENDICES A MARKETING SURVEY 71
APPENDICES B PROCESS OF PROGRAMMING MICROPCHIP 74
APPENDICES C SECOND STEP IS TO CONVERT THE HEX FILE IN
TO MICROCHIP 82
APPENDICES D CIRCUIT BOARD DIAGRAM AND CONCEPTUAL
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LIST OF TABLES
2.1 Comparison of material used to make bento boxs and accessories.
3.1 Two type of meal box from marketing to compare thermal heated lunch box
3.2 HOQ of streamlined configuration as applied to a thermal heated-lunch box
3.3 Weighted decision matrix for thermal heated lunch box 3.4 Gantt chart
5.1 Table of overall performance of thermoelectric cooler peltier
5.2 Temperature after power is cut off\ 5.3 Thermostat effect
5.4 Performance of prototype
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LIST OF FIGURES
1.1 Lunch box for children and aduit. 2.1 Thermoelectric cooler peltier.
2.2 Schematic diagram of a thermoelectric cooler. 2.3 Heat transfer through wall.
2.4 Heat transfer through air to wall 2.5 Aluminium foil
2.12 Liquid crystal display (LCD) 2.13 Lithium ions cell
2.14 LM35 Temperature sensors
2.15 Temperature contour inside the furnace 3.1 Schematic diagram using Solid work 3.2 Material Selection Process Flow 3.3 CFD Simulate Process Flow
3.4 Concept and ideal Fabrication
3.5 Thermal heated lunch box completed assemble
3.6 Pic controller to control electronic component 3.7 Programmer flow chart
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4.1 Fabrication process flow 4.2 Dimensioning to aluminum foil 4.3 Aluminum foil (inner wall) been cut 4.4 Aluminum foil (top section) been cut 4.5 Aluminium foil (soft and thin) to wrap
4.14 soldering extension cable 4.15 Inner wall view
4.16 Electronic component wit peltier 4.17 Top view of prototype with cover off 4.18 Side view of prototype
4.19 Front view of prototype 4.20 Testing on the prototype
4.21 Light show the system is functioning
4.22 Red light indicate temperature has reached below 400C 5.1 Experiment on performance of thermoelectric cooler peltier 5.2 Overall performance of thermoelectric cooler peltier
5.3 Temperature after power is cut off 5.4 Thermostat effect
5.5 CFD simulate of heat
5.6 Temperature versus position 5.7 Power against time
5.8 Battery pack being changed 5.9 Isometric view of prototype 5.10 Explode view of prototype 5.11 Inner view of prototype
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5.13 Exploded view of prototype in Solid work software 5.14 Mplab software
5.15 PCkit software
5.16 View of heat component in solid work software 5.17 Inner view of electronic component and heater section
5.18 Picture shows the different of the conceptual and actual prototype 5.19 :Picture show end product
A1 Survey on the thermal-heated lunch box A2 Gender servey on this project
A3 Know the avantages of this project A4 Understand of this project
A5 C program in MP lab A6 PIC programming
A7 Save the file and export is as hex file A8 Export hex file
A9 Install the chip on the hardware slot A10 Connect the hardware to the computer A11 PCkit software
A12 Import the hex file to PCkit A13 Write the code to the chip
A14 Install back the chip to the circuit board A15 Circuit diagram
A16 Isometric view of prototype A17 Three section view of prototype A18 Explode view of prototype A19 Inner view of prototype
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LIST OF ABBREVIATION
ΔT - temperature difference
q - rate of heat transfer per unit area
Q - rate of heat transfer
U - internal energy ; overall heat transfer coefficient
A - area
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CHAPTER 1
INTRODUCTION
1.0 INTRODUCTION TO LUNCH BOX
Lunch box is a tool kit which able to store up food or meal for later consumption. It is capable of protecting the food from dust as well as water and delaying the time of the food becomes spoilt.
The concept of lunch box has been around for very long and less information is know on who did invent it, but it plays significant role in our life especially during work or school. School children use lunch box to pack lunch or snack prepared at home by their family. Common modern form of lunch box appeared in small case with clasp, handle and it is usually printed with colorful image based on children show or film character for example superman, Snoopy, ultra man and etc. For working adult, they mostly prefer using plain aluminum or tin made lunch box with simple graphic only show in Figure 1.
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There are certain health issues regarding use of vinyl lunch box. Center for Environmental Health discovered that many popular vinyl lunch boxes contained dangerously high levels of lead in 2002. Many manufacturers begin inspecting their product lead lever and labeled lead free. Studies have shown certain plastic made plastic Lunch box Polyethylene, Polypropylene and Polycarbonate from biphenyl will cause certain disease, and one of which is believed to be cancer. All lunch boxes should undergo safety standard rule for food container before commercial use. Right use of lunch box and plastic container will prevent unfortunate incident.
Improper dispose of lunch box will contribute to pollution which will endanger ecology. Some plastic made lunch box will not dispose easily and will bring harm to the animal and aquatic once being consumed. All users should have environment awareness and understand the circumstance. However, lunch box evolves from time to time and even now it still plays an important role in human life having a great bond with human activity. (Debra Ronca)
1.2 OBJECTIVE
1. To design an economical thermal lunch box that can obtain the freshness of meal in longer hours.
2. To develop an environmental friendly thermal lunch box that can be used in everyday life.
1.3 PROJECT SCOPE
1. PIC system is used to control the temperature in the container.
2. Developing CFD simulation to show the heat circulation inside the thermal lunch box.
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1.4 NEED OF RESEARCH
Due to the advancement in the city, human’s lifestyle become hectic each day. Many people cannot even enjoy a proper meal as they need travel to other place to work with people living in hectic working schedule time becomes very important factor in order to success and time not enough for them.
As an alternative, take away or self prepare meal become one of solution. Food storage concept become very essential in life and lunch box or food container become very popular among people in now. But most of the people missed their lunch time and leave their meal, sooner they found their food not fresh. For long term it will affect the health of human. An innovative a thermal heated lunch box to solve this problem.
1.5 BASIC CHARACTERISTIC OF LUNCH BOX
Characteristic of lunch box is important for further research and product development. Therefore, a continuous study is required in order to an understanding to enhance a creative development. There are a few characteristics can be identified in a basic lunch box, which are:
1.5.1 Material
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1.5.2 Storage space
Storage space refer to the capacity or volume that a lunch box capable to contain. Different people required different volume of food per meal. From the research female adult consume less food than male adult. For children, they only require half of meal of the adult. As for result, different sizes of lunch box appear in the market. (Science daily)
1.5.3 Food protection
Food protection characteristic in the lunch box is another feature should be considered. It refers to the capability to cover the food and protect it from dust or water which will spoil the food. It is essential to separate the food from contacting outside air because the air contains dust or bacterial which will affect the tastiness and freshness of food. The lunch box should also come with an air seal or leak proof feature to ensure it is fully protected from rain or water.
1.5.4 Temperature resistance
Temperature resistance on plastic lunch box is the ability to withstand heat and does not create chemical reaction, the temperature between 350C - 45 0Cis good temperature resistance. If the temperature resistance is not high enough it may react and endanger human health when using it. So it is very important to undergo serious inspection and lead lever check before putting out to market.
1.5.5 Thermal insulation
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longer period of time. Material selection become important as it will affect the rate of heat transfer.
1.5.6 Mobility
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CHAPTER 2
LITERATURE REVIEW
2.1 INTRODUCTION
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2.2 THERMOELECTRIC COOLER PELTIER
Thermoelectric cooler peltier is an electronic component show in Figure 2.1, uses the peltier effect to create a heat flux between the junction of two different type material that is by n-type and p-type semiconductor show in Figure 2.2, which heat transfer is from one side to other side against the temperature from cold to hot. The advantages of thermoelectric cooler peltier are no vibration, low maintenance fee and high reliability. ( Huang, Yen and And Wang 2004).
Figure 2.1: Thermoelectric cooler Peltier.
Figure 2.2: Schematic diagram of a thermoelectric cooler.
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2.3 THERMODYNAMIC (HEAT TRANSFER)
Heat transfer is where the heat tends to move from a higher temperature region to a lower temperature region. Conduction occurs when there is an exchange of energy by direct interaction between molecules of a substance containing temperature differences in the form of gases, liquids or solid which has a strong basis of molecular kinetic of physic. ( Eastop and McConkey, 1993 )
2.3.1 Fourier law of heat conduction
When there is a temperature difference appears in the body, the heat will transfer from a hot region to a cooler region. This unique phenomenon is known as conduction heat transfer, and it is also described by Fourier’s Law.
The vector q in the equation represent the heat flux for a given temperature profile T and k for thermal conductivity. In the equation the negative sign is where heat flows down the temperature gradient. According Fourier Law of cooling, Heat is transfer within a solid material. Derivation of the equation is shown as below,
